Switching processing can be completed for a packet by a fabric interface controller (FIC) and a fabric element (FE). The FIC is generally located on a line processing unit (LPU), and the FE is generally located on a switch fabric unit (SFU) independent of the LPU. In the prior art, in a large-capacity switching system, each FIC on an LPU is connected to each FE on all SFUs. According to the connection relationship, full SFU configuration is required regardless of the number of LPUs to allow a packet to be switched from a port of an LPU to any other port. For example, in the case of full configuration, the number of SFUs is 3. In this case, three SFUs need to be configured no matter whether one, two, or more LPUs exist.
However, a user generally performs expansion gradually when using a fabric. Only a few LPUs need to be configured during initial configuration, and expansion may be performed to increase the number of LPUs after several years. In this case, if full SFU configuration is performed during initial configuration, costs during initial configuration are relatively high because the SFU is a costly device.